Experimental investigation on the fouling mitigation and enhancement of heat transfer in a double-pipe heat exchanger in the presence of low-frequency vibrations

Purpose Formation of fouling is a serious concern in heat exchanger usage for long run when it is operated with nanofluids. The deposition of the fouling layers significantly reduces the thermal performance of the heat exchanger during the long runtime. The purpose of this study is to give a prospective solution to mitigate this fouling challenge. Design/methodology/approach This study made a special emphasis on the effect of fouling formation due to the presence of nanoparticles inside the inner pipeline of the heat exchanger. A novel experimental setup – comprises two concentric pipes – is considered in which flow of hot and cold fluid occurs. The setup consists of a vibrator which is equipped to the external pipe for inducing low-frequency vibrations up to 1,250 Hz. The influence of low-frequency vibrations will enhance the heat transfer in a double-pipe heat exchanger at varied cold and hot fluid flow in the range of 0.25–1 L/min. Findings The effectiveness of the heat exchanger considered is compared in terms of overall heat transfer coefficient with and without presence of low-frequency vibrations. Results showed that significant enhancement of heat transfer occurred in presence of ultrasonic vibrations. Originality/value It is found that the heat transfer enhancement is raised up to 40% under the presence of low-frequency vibrations as compared to the experiments which were carried out without the presence of vibrations. Finally, an uncertainty analysis has been carried out to validate the experimental investigation performed.